Chapter 85 – Eyelid Retraction

• Deviation from the normal position of the upper or lower eyelid margin with respect to the limbus of the eye.

KEY FEATURES

• Upper eyelid margin above superior corneal limbus.

• Lower eyelid margin below inferior corneal limbus.

ASSOCIATED FEATURES

• Secondary epiphora.

• Corneal exposure.

• Dry eye symptoms.

INTRODUCTION

At first glance, eyelid retraction may appear to be an uncomplicated anatomic variant of eyelid position. The differential diagnosis, however, is extensive and encompasses congenital abnormalities, systemic infectious and inflammatory processes, degenerative disease, involutional changes, and traumatic or postoperative repercussions.

Management options for eyelid retraction may be as varied and complex. Medical treatment may return the eyelids to their normal position. Other cases require surgical repositioning to restore normal eyelid anatomy.

PREOPERATIVE EVALUATION AND DIAGNOSTIC APPROACH

The Ophthalmic History

Eyelid retraction is defined as a deviation from the normal position of the upper or lower eyelid margin with respect to the limbus of the eye. Simple observation of most normal individuals confirms that the upper eyelid margin usually rests 1–2?mm below the superior limbal border. The lower eyelid margin rests at the level of the inferior limbus. Elevation of the superior eyelid margin above this level or depression of the lower eyelid margin below this level is a variation from the vast majority of the population. Furthermore, retraction may be unilateral or bilateral. In most cases, this retraction manifests itself as a visible zone of sclera above or below the limbal margin.

Mild retraction of the lower eyelids may occur as a variant of eyelid position in otherwise normal individuals. Individuals with axial myopia, familial congenital shallow orbits, or maxillary hypoplasia often have modest (1–2?mm) lower eyelid retraction. Involutional changes with laxity of the tarsal canthal tendons also presents with lowering of the inferior eyelid margin.

During the initial evaluation, a careful history of the presentation of retraction should be taken. The distinction between an acute and a chronic process as perceived by patients is not always helpful because it is common for them to remain unaware of long-term subtle changes in eyelid position. An extensive medical history helps to establish any further tests required to confirm a diagnosis. Particular attention should be directed to symptoms of thyroid disease. Several other rare causes are discussed in this chapter to widen the differential diagnosis for the practicing physician.

The Ophthalmic Examination

A complete periocular examination is essential to form a diagnosis. It is important to measure and document the position of the upper and lower eyelids with respect to the limbus. Other helpful measurements should include the palpebral fissure heights, the degree of lagophthalmos or lid lag on downgaze, levator muscle function, and the distances from eyelid margin to central corneal reflex; exophthalmometry can also be used. Further examination of the eyelid position should be completed in all fields of gaze and with movement of the mouth to uncover possible traumatic rectus muscle entrapment, Graves’ disease, cranial nerve regeneration, jaw-winking ptosis, and Duane’s syndrome. Traction on the eyelids may uncover fibrosis and scarring. Forced duction testing is helpful to diagnose the existence of fibrotic or incarcerated rectus muscles. Palpation of the globe in conjunction with exophthalmometry may be used to assess axial myopia or reveal the presence of orbital tumors. Palpation and observation of the orbital rims may expose old bone trauma or maxillary hypoplasia. Traction on the lower eyelid tissue is helpful in diagnosing involutional laxity and cicatricial changes in the anterior and posterior eyelid lamellae.

Pseudoretraction may be seen in cases of contralateral eyelid blepharoptosis with a Hering effect. In the presence of unilateral ptosis, equal central nuclear outputs to both levator muscles may result in elevation and retraction of the previously normal opposite eyelid. Pseudoretraction of the elevated eyelid is suggested when digital elevation of the more ptotic lid results in lowering of the retracted lid. Similarly, digital closure of the retracted lid results in elevation of the opposite ptotic eyelid. Examination of ocular and orbital structures may detect several other causes of the aberrant eyelid position. Buphthalmos, intraocular tumors, enlargement of the rectus muscles, or orbital tumors may present with unilateral or bilateral proptosis and eyelid retraction. Orbital apex crowding, from either a mass lesion or enlarged infiltrated rectus muscles, may result in increased intraocular pressure and abnormal visual fields. This phenomenon may also yield abnormal results for optic nerve function and optic nerve head edema or pallor on ophthalmoscopy.

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Ancillary Tests

Orbital examination may be augmented by ultrasound or radiological studies such as computed tomography or magnetic resonance imaging (MRI). The latter studies are particularly helpful in the diagnosis of Graves’ disease, orbital trauma, and orbital tumors. Classically, there is enlargement of the belly of the rectus muscle in Graves’ disease. Enlargements of the inferior rectus muscle and medial rectus muscle are most common, although enlargement or infiltration of all rectus muscles may occur unilaterally or bilaterally. Thyroid function tests are commonly ordered in cases of upper eyelid retraction. They may not clearly rule out thyroid disease because Graves’ disease can be present in euthyroid patients. Initial tests should include serum thyroxine, triiodothyronine (T3 ), thyroid-stimulating hormone levels, and resin T3 uptake. Euthyroid patients who have suspected Graves’ disease may warrant further testing with antithyroglobulin and antimicrosomal antibodies. Elevated thyroid antibody titers may confirm a thyroid-related rectus muscle infiltrative process, even in the presence of normal thyroid hormone levels. If all of these tests remain normal, a thyrotropin-releasing factor test may further refine the diagnosis, although in some cases of euthyroid Graves’ disease all chemical diagnostic tests are normal.

DIFFERENTIAL DIAGNOSIS

The most definitive work on the differential diagnosis and classification of eyelid retraction has been published by Bartley.[1] A schema of three main classes has been proposed, which includes neurogenic, myogenic, and mechanistic causes. As with all such classification schemata, there are limitations to accommodating so many diverse disease processes in only three or four groups.

Neurogenic Retraction

Neurogenic eyelid retraction ( Box 85-1 ) encompasses a diverse group of diseases within which are several well-known causes, such as dorsal midbrain syndrome resulting in Collier’s sign. [2] [3] [4] Other more common neurogenic causes include aberrant regeneration or innervation of the oculomotor nerve[5] and Marcus Gunn (jaw-winking) syndrome. [6] [7] [8] [9] [10] [11] Orbital floor fractures may fall into both the neurogenic and mechanistic classes. In the first case, retraction is associated with increased innervation to the

From Conway ST. Lid retraction following blow-out fracture of the orbit. Ophthalmic Surg. 1988;19:279–81.

superior rectus and levator muscles in an attempt to overcome mechanical restriction. [12] In the second case, retraction is caused by traction on the connective tissue sheath or a postoperative complication in the lower eyelid after repair of a blowout fracture. [13] Bartley[1] lists 39 separate causes for neurogenically induced retraction of the eyelids.

One important subgroup in this neurogenic category is the phenomenon of pseudoretraction associated with ptosis of the contralateral upper eyelid. This subgroup is significant because pseudoretraction may be seen in 66.7% of ptosis patients.[14] In these cases, Hering’s law, or effect, induces an artificial elevation of the contralateral upper eyelid, often misdiagnosed in much the same manner that unilateral enophthalmos is mistaken for contralateral proptosis. Surgical correction of the ptotic eyelid frequently unmasks ptosis in the previously retracted eyelid. Pseudoretraction has also been noted in association with thyroid orbitopathy,[15] although many of these cases may be caused by levator aponeurogenic ptosis.

Myogenic Retraction

The myogenic eyelid retraction ( Box 85-2 ) class is the smallest in the Bartley classification,[1] although it includes Graves’ disease, which is undoubtedly the most common cause of true upper eyelid retraction (see Box 85-3 ). Controversy remains over the cause of upper eyelid retraction associated with Graves’ disease. Proposed mechanisms for retraction include orbital proptosis secondary to enlargement of the rectus muscles, levator and Müller’s muscle infiltration with fibrosis, excessive sympathetic innervation, abnormal adhesions between the levator and adjacent tissues, and fixation duress.[16] The last and less well-known cause occurs when fixating with an eye that has inferior rectus muscle restriction. The result is excessive stimulation of the ipsilateral superior rectus levator complex.[17] [18] Thickening of the levator muscle seen on T1-weighted sagittal MRI in patients with Graves’ disease is closely associated with upper eyelid retraction, which has also been suggested as a causative factor for retraction.[19]

Other important entrants in the myogenic subgroup are myasthenia gravis, botulinum toxin injection, and postsurgical complications of vertical rectus muscle recessions, ptosis overcorrection, and defects following enucleation. Myasthenia gravis is known more as a cause of myogenic ptosis than of eyelid retraction; however, one study showed that 4 of 150 patients with

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this disease had eyelid retraction.[20] This phenomenon may be truly pseudoretraction rather than an intrinsic problem associated with myasthenia gravis. Botulinum toxin injection is most likely to result in lower eyelid retraction secondary to loss of orbicularis oculi muscle tone. The postsurgical complications in general have obvious causes, with correction by partial reversal of the initial surgery.

Mechanistic Retraction

The last major classification, referred to as mechanistic ( Box 85-3 ), comprises a vast array of causes primarily related to architectural changes in the eyelid structure. This is also probably the major cause of Graves’ eyelid retraction. These changes may be congenital, cicatricial, traumatic, neoplastic, or postoperative. In theory, diagnosis in this category is simpler than in the categories of neurogenic and myogenic causes. Most diagnoses are straightforward and based on obvious morphological changes in the patient, such as craniosynostosis. Consequently, repair of the anatomic defect should in many cases correct the eyelid malposition.

Miscellaneous Causes of Retraction

A miscellaneous category ( Box 85-4 ) has also been developed for cases in which eyelid retraction is reported but no clear explanation of cause and effect can be determined.

From Conway ST. Lid retraction following blow-out fracture of the orbit. Ophthalmic Surg. 1988;19:279–81.

ALTERNATIVES TO SURGERY

Eyelid retraction may be related to systemic disease, such as Guillain-Barré syndrome or myasthenia gravis, in which case it should be treated using systemic medication if appropriate. Other cases may respond to topical treatments, such as corticosteroid ointment for atopic dermatitis. Discontinuation of topical drops, such as apraclonidine, may also resolve drug-induced retraction. Eyelid retraction associated with Graves’ disease may show some improvement following high-dose oral corticosteroids or radiotherapy used in the treatment of compressive optic neuropathy or severe orbital congestion.

ANESTHESIA

As with all surgery involving alterations in upper eyelid position, it is best to perform corrections of eyelid retraction under local anesthesia whenever possible. This allows more precise adjustment of eyelid height. The use of epinephrine (adrenaline) in the local anesthetic mixture stimulates Müller’s sympathetic muscle; if this muscle is left intact, some compensation should be allowed for the loss of Müller’s tone following the procedure.

SURGICAL TECHNIQUES

Surgical management of eyelid retraction can be separated into direct and indirect approaches. The direct method specifically addresses abnormalities of eyelid tissue. This approach can be further divided into treatment of upper eyelid and that of lower eyelid retraction. The indirect approach addresses a fundamental architectural abnormality of the orbit responsible for the retraction, such as seen in Paget’s disease of bone or in craniosynostosis. Other indirect surgical treatment may involve excision of orbital neoplastic processes responsible for proptosis and subsequent eyelid retraction.

Levator Aponeurosis Recession with Excision of Müller’s Muscle

The aponeurotic approach to this surgery begins with marking the appropriate eyelid crease. The skin beneath the crease is infiltrated with a small amount of local anesthetic, such as 2% lidocaine (lignocaine) with epinephrine 1:100,000. After adequate anesthesia is achieved, the crease is incised and dissection continues through the orbicularis oculi muscle to the septum. The septum is identified and incised 1–2?mm above its insertion into the aponeurosis. Orbital fat can be gently pushed superiorly with cotton-tipped applicators. The inferior attachments of the aponeurosis are freed from the superior border of the tarsus. Dissection under the aponeurosis and above Müller’s muscle is continued up to Whitnall’s ligament. A small amount of local anesthetic can be injected into Müller’s muscle at this time. Müller’s muscle is excised from the superior border of the tarsus up to the level of Whitnall’s ligament.

The patient’s corneal shield is removed, and the patient is elevated to a sitting position. The position of the eyelid relative to

Miscellaneous Causes of Eyelid Retraction

• Optic nerve hypoplasia

• Microphthalmos

• Down syndrome

• Essential hypertension

• Hepatic cirrhosis

• Meningitis

• Sphenoid wing meningioma

• Lymphoma in superior cul-de-sac

From Conway ST. Lid retraction following blowout fracture of the orbit. Ophthalmic Surg. 1988;19:279–81.

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the superior limbus is evaluated. The lid should be ptotic, and the procedure now becomes a ptosis repair. The aponeurosis may be advanced to tarsus or sutured directly to conjunctiva so that the eyelid margin lies at the appropriate height. In the case of conjunctival sutures, there is a risk of corneal abrasion. Attention is directed toward correcting any medial or lateral flare by severing attachments of the medial and lateral horns of the levator. Tightening the attachment of the superior lateral canthal tendon also improves lateral scleral flare or exposure. Placement of a Frost suture at the completion of the procedure may assist in prevention of short-term recurrence of retraction.

Placement of spacers to lengthen the upper eyelid has been recommended, most commonly contralateral tarsus and autologous sclera.[21] [22] However, this has not met with the same success as their use to raise the lower eyelid position. The primary problem associated with spacers in the upper eyelid is the obvious increased risk of corneal irritation and abrasion. Mourits and Koornneef [22] reported a series of 62 consecutive patients in whom sclera was used as a spacer. In this series only 50% of patients had an acceptable result after one operation. The main complications were persistent temporal retraction and nasal overcorrection. Mourits and Koornneef[22] concluded that no distinct advantages could be found in the use of sclera as an upper eyelid spacer over other standard lengthening techniques.

Lower Eyelid Recession with Spacer Graft

In some cases of involutional or cicatricial lower eyelid retraction, repair of canthal tendon laxity and anterior lamellar contraction needs to be addressed. Lateral canthal tendon support can be augmented by several surgical procedures, including the lateral tarsal strip or sling.[23] [24] Anterior lamellar augmentation is performed with split- and full-thickness skin grafts as well as orbicularis oculi muscle transposition. However, in the presence of proptosis, the primary emphasis in treating lower lid retraction is to place a spacer in the posterior lamella to lengthen the retractors and give eyelid support. Numerous materials have been utilized for this purpose, including auricular cartilage, [25] [26] [27] [28] nasal septal cartilage,[29] autologous sclera, [30] [31] [32] costochondral cartilage,[32] fascia lata, [33] [34] [35] autogenous tarsus,[36] and hard palate.[36]

There are advantages and disadvantages to the harvesting and usage of each of these tissues. Cartilage, whether from the ear or the nasal septum, is relatively easy to harvest. The most significant limitation to cartilage in lower eyelid reconstruction is its lack of pliability, which can produce disfiguring contour abnormalities. Sclera is readily available through the eye bank, but unpredictable rates of shrinkage limit its value as a lower eyelid spacer. Reoperation for recurrent eyelid retraction is consequently higher when sclera is used. Costochondral cartilage is more difficult to obtain than other grafts. Fascia lata is available as autologous tissue but lacks the rigidity necessary for lower eyelid support. Autologous tarsus is an excellent spacer but is available in rather limited quantities because excessive harvest of upper eyelid tarsus may distort the position of the donor eyelid. Hard palate mucosa provides one of the optimal spacers for several reasons. The tissue is easily harvested and is available in adequate quantities for most cases of lower eyelid retraction. This tissue is rigid enough to support elevation of the inferior tarsus and pliable enough to avoid contour abnormalities.

Hard palate mucosal grafts are harvested by first infiltrating local anesthetic into the hard palate in the posterior region of the transverse palatine folds and adjacent to the palatine raphe. Excision of the graft, which includes mucosa, submucosa, and a small amount of fat, is completed with straight and angled surgical blades. A No. 66 Beaver blade is very helpful in this excision. Gentle cautery is used in the graft bed. The surgeon should be careful to avoid injury to the anterior palatine artery as continued postoperative bleeding can occur. The mucosal graft can vary in height and width with an average graft size of about 5?mm by 20?mm. The graft bed may be left to heal without treatment or packed and covered with a custom-molded dental plate. The latter apparatus adds time and cost to the procedure and may not completely resolve the postoperative pain associated with surgery on the palate.

More recently, a high-density porous polyethylene graft has become available for lower eyelid retraction. It is easily inserted through a small lateral eyelid incision and placed into a pocket between the orbiculans muscle and orbital septum. Although long-term results are not yet available, early indications suggest that this may be a useful procedure.

Placement of the graft requires an incision into the lower eyelid just below the tarsal border. The graft is trimmed to the appropriate thickness, removing excess fat or submucosa. Suturing the graft is completed by running a dissolvable suture, such as plain gut, and burying the knots. Frequently, this surgery is done in conjunction with a lateral canthal tightening procedure.

COMPLICATIONS

The most common complications of surgery for eyelid retraction are undercorrection and overcorrection. The postoperative eyelid position can be highly variable despite a surgeon’s best efforts and careful preoperative and intraoperative assessments. Continued flare of the lateral upper eyelid may not be so much a complication as an incomplete treatment of this problem. However, both the patient and the surgeon may see this as a less than optimal result. Lower lid elevation can be limited by the height of the spacer, and in most cases only a finite amount of spacer is available from any one source. Postoperative shrinkage of a spacer such as sclera is well known and unpredictable, potentially resulting in recurrence of the retraction. Also, some spacers such as nasal or auricular cartilage are difficult to contour and can lead to a bulky lower lid appearance. Spacers in either the upper or lower eyelid can cause epithelial erosion of the corneal surface.

OUTCOMES

In the majority of cases, the eyelid can be restored to a normal position and results in better protection of the cornea. In patients with Graves’ disease, recession can also mask some degree of proptosis.